Fluid pumps are available in a number of different configurations and are used for a multitude of different applications. In many of these applications, the internal components of the pump require some sort of lubrication. One of the most common ways to provide this lubrication is to expose the internal components of the pump to a lubricant, such as oil. However, because the fluid that is being pumped is often a different fluid than the lubricant, care must be taken to ensure that the pumped fluid and the lubricant do not mix.
Such contamination can be avoided in different ways, depending the on the configuration of the pump being used. One relatively common pump configuration utilizes a primary drive shaft that includes a driven member (e.g., a member, such as a gear, that engages the power source that provides the power to operate the pump) on one end and a working member (e.g., an element or elements, such as an impeller or a set of gears, that cooperate together to provide a pumping action) on the other end. The drive shaft is generally supported within the pump housing by at least two bearings, one provided near each end of the drive shaft. The end of the drive shaft with the driven member is often exposed to a lubricant (e.g., oil) while the end with the working member is exposed to the fluid that is being pumped. To avoid contamination of the pumped fluid and oil with one another, at least one seal that keeps the lubricant and pumped fluid separate is generally provided at some point along the drive shaft. The seal is normally provided on the side of the bearing that is opposite the driven member to ensure that the bearing near the driven member of the drive shaft is lubricated.
For pumps with such a configuration, the lubricant (e.g., oil) may become substantially trapped between the bearing and the seal. Friction with the rotating drive shaft and seal may cause this trapped volume of oil to overheat. When the oil overheats, carbon particles may be generated within the oil that, over time, may lead to seal or shaft wear and eventually leakage of oil between the shaft and the seal.
The disclosed pump is directed to overcoming one or more of the problems set forth above or other problems.